The system is comprised of several sub-systems, which are described in detail below. The system is capable of identifying vehicles for which no toll transaction occurred, or where the toll transaction could not take place properly.
Tolling stations are built on the tolled road network and they are equipped with antennas that enable communication between a tolling station and a premid onboard unit to take place.
When passing through a toll gantry, an acoustic signal from the premid alerts the driver that the toll has been registered properly The tolling process is automatic.
Enforcement stations are equipped with technology to check whether vehicles have premid units installed, whether they are installed properly, and to check toll payments.
In the event of any discrepancies, the information is forwarded to the enforcement centre of the electronic tolling system, including an automatically acquired image of the vehicle in question. Enforcement centre staff will verify this information. If a tolling offence is confirmed, the information will be forwarded to mobile enforcement units, who will stop the vehicle and impose a penalty. The vehicle can be even impounded.
Portable enforcement devices
In addition to the stationary gantries, there are also portable devices that are not attached to one specific spot and can be deployed to various sections of a road.
Mobile enforcement complement the functions of stationary and portable enforcement devices. They are performed by the General Directorate of Customs of the Czech Republic (Generální ředitelství cel ČR), which the central office of the electronic tolling system notifies about all offences immediately.